Portio Research takes an optimistic outlook for Mobile Messaging Futures 2007 - 2012. It upwardly revises previous predictions from 2005 - SMS growth has not flattened out in mature markets but continued to boom whilst the US market has grown much faster than expected. By 2012, global SMS revenue will reach $67b, driven by 3.7 trillion messages.
The report states that just in Asia 450 people every minute will get their first mobile phone - and the adoption will tick along at this rate for the next 6 years.
Portio reckons that Mobile IM will supplant SMS as the principle messaging service by 2011. I strongly disagree - because IM currently requires opt-in. Admittedly, interconnectivity between IM providers has occurred technically, but the mass market certainly hasn't appreciated this yet, nor is IM embedded at all with the weak exception of the US.